Now, Craigslist is cooperating with a probe into deceptive apartment advertising by the New York City Department of Consumer Affairs, the site’s founder, Craig Newmark, said on Friday. The FBI did not return calls seeking comment.

The story started in early November, when Bovino, a senior economist with Standard & Poor’s, got the first call from a man following up on the ad. Her real name had been used, as well as the correct address on Manhattan’s stylish Upper West Side and a picture of her brownstone facade – plus bogus photos of the interior. “That was not my bathroom!”

The too-good-to-be true ad asked for $1,500 for the one-bedroom with fireplace, utilities included. (Other single bedroom apartments in the neighborhood go for two, even three times, that much.)

And the ad provided some unusual information: The apartment owner claimed to be deaf and mute, living in California, and therefore could not speak to prospective renters. The apartment, and the keys, could be seen only after a fee was fronted.

People desperate to land something affordable started stopping by, unannounced. Bovino’s apartment in fact was for sale, for real, and she was moving to Brooklyn.

She correctly suspected that the con artist exploited that real ad to create the fake rental classified. “I was concerned. This wasn’t a joke anymore,” said the native New Yorker.

She contacted the FBI about a week after the first call, reporting the case to the agency’s Internet Crime Complaint Center, a clearinghouse for Web-based Internet fraud complaints.

And the 41-year-old native New Yorker got to work – trying to solve the case on her own.

First, Bovino got herself a new e-mail address. “I called myself Beth Max – if you turn Max around, it sounds like ‘scam.”‘

She got a written reply that said: “I would love to speak with you by phone but I can’t because I’m a deaf-mute person and I am teaching in CA for a deaf-mute school.”

She also contacted Craigslist and asked that the fraudulent ad be removed. It was – for awhile. Then the scammer would place a new ad – again, and again, and again, with slight changes in the wording or a lower price.

“I got a $100 discount to rent my apartment,” said Bovino.

And the phone calls kept coming to her, through New Year’s.

Authorities haven’t yet cracked the case, she said, and the ad is still up, in a mutated form.

“Last week, I think it was $1,000. I thought, ‘Why don’t I apply?”‘ she joked.